A computer cabinet is an enclosure which holds most of the parts of a computer system. These parts include central processing unit (CPU) boards, peripheral boards, disk drives, power supplies, fans, and cables. Typically, computer cabinets are tightly packed in order to keep the size of the system small enough to fit on or under a desk. The parts are attached to the computer cabinet with fastening hardware such as screws, which need to be small because of the tight fit inside the computer cabinet.
One problem with using screws to attach the computer system parts to the computer cabinet is that such screws may be difficult to access during the manufacturing and servicing of the computer system. When a field engineer or technician replaces a part which is fastened to a computer cabinet with screws, he typically reaches into the computer cabinet with a screwdriver in order to remove the screws which attach the part to the computer cabinet. Even if the technician can access the screws easily enough to unscrew them, he may drop the screws into the computer system. Then the technician must spend time retrieving the screw from inside the cabinet. If the screw is not retrieved, it may cause a short circuit on one of the boards depending on where the screw ends up. For at least these reasons, replacing parts in the computer system is a time-consuming and frustrating process.
The process may be particularly difficult and time-consuming if the number of fastening screws is high. Mounting a storage device such as a disk drive typically requires at least four screws. Two screws are positioned on each side of the disk drive, one toward the front and one toward the back, in order to mount the disk securely to the chassis. The screws are usually very small, therefore making it difficult for a technician to hold the screws in position while screwing them in with a screwdriver. The screws are inserted into holes which are on the disk drive assembly and on the chassis to which the disk drive assembly is being attached. The holes are difficult to align because they are also typically very small. Also, if the tolerances are incorrect, typically due to manufacturing defects, the holes may not line up exactly, making it difficult to insert the screw.